Man, I am such a genius sometimes. So it seems that whenever you upload a world from your local to the realms service, there is a glitch that occurs that flips every cheat rule that is set by default to the world (when the "Activate Cheats" setting is off) such as daylight cycle, mob spawning, etc. When you upload a world, even if the world is completely survival for achievements, it will still allow you to unlock them, but the game will have its default 'cheat' settings flipped (from true to false or false to true), I know this because the game was on peaceful and keep inventory was on, even though my cheats were off, but I could still earn trophies, and the only way to go back to normal is to active the cheats to flip the settings back to normal, but removes the achievements from the world. So once this glitch occured, my simple fix was to download the world back on my phone, and simply reupload that same world (with the flipped settings glitch) onto the second world space in the realms to REFLIP the default 'cheat' settings back to normal, and it worked. You will know it worked because everything under the "Activate Cheats" toggle except 'keep inventory' and 'command blocks enabled' should be toggled on. This is a fix for those that don't want to screw their world by turning on cheats and keep them eligible for achievements, but the glitch happens in the upload and possibly in the download process as well (although i've only seen it happen in the upload process) where it flips the default cheat settings for no reason. Note: when you are going to try to reflip the settings back to normal, make sure you have reset the world on the realm slot, because those default settings will transfer to your uploaded world (at least thats what it seems like).
Update: ive done some testing, and it might do the settings flip glitch when its a world being uploaded to a slot in the the realm that DOESNT have a world on it (not even a new world; on the first time upload). The same fix will work if the glitch happened to your world as long as you download the world, then reset the world in the realm before the reupload.
Man, I am such a genius sometimes. So it seems that whenever you upload a world from your local to the realms service, there is a glitch that occurs that flips every cheat rule that is set by default to the world (when the "Activate Cheats" setting is off) such as daylight cycle, mob spawning, etc. When you upload a world, even if the world is completely survival for achievements, it will still allow you to unlock them, but the game will have its default 'cheat' settings flipped (from true to false or false to true), I know this because the game was on peaceful and keep inventory was on, even though my cheats were off, but I could still earn trophies, and the only way to go back to normal is to active the cheats to flip the settings back to normal, but removes the achievements from the world. So once this glitch occured, my simple fix was to download the world back on my phone, and simply reupload that same world (with the flipped settings glitch) onto the second world space in the realms to REFLIP the default 'cheat' settings back to normal, and it worked. You will know it worked because everything under the "Activate Cheats" toggle except 'keep inventory' and 'command blocks enabled' should be toggled on. This is a fix for those that don't want to screw their world by turning on cheats and keep them eligible for achievements, but the glitch happens in the upload and possibly in the download process as well (although i've only seen it happen in the upload process) where it flips the default cheat settings for no reason. Note: when you are going to try to reflip the settings back to normal, make sure you have reset the world on the realm slot, because those default settings will transfer to your uploaded world (at least thats what it seems like).
Update: ive done some testing, and it might do the settings flip glitch when its a world being uploaded to a slot in the the realm that DOESNT have a world on it (not even a new world; on the first time upload). The same fix will work if the glitch happened to your world as long as you download the world, then reset the world in the realm before the reupload.